The invention relates in general to integrated circuit packages and compact assemblies thereof (e.g., modules), as well as computer hardware products comprising such assemblies and related fabrication methods. It is, in particular, directed to dense assemblies of integrated circuit packages that comprise integrated circuit chips mounted on printed circuit boards.
This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section.
Printed circuit boards (PCBs) are used to support and electrically connect various electronic components. PCBs use conductive tracks and contact pads, which are typically etched from a copper sheet laminated onto a non-conductive substrate (typically a FR-4 glass epoxy). PCBs can be single sided or double sided. One also knows multi-layer PCBs, which allow for higher component density.
Higher integration and speed of microprocessors and memory requires compact packaging. Of particular importance is the reduction of wire length between devices. High density interconnect boards have been proposed, which comprise blind and/or buried vias and offer higher circuitry density than traditional circuit boards. Beside, rectangular assemblies of PCBs exploit the third dimension, allowing PCBs (or IC packages comprising PCBs) to be placed close to each other. PCBs may for instance be grouped in horizontal or vertical arrangements using sockets to maintain and electrically connect them to, e.g., a base board.
For example, one knows storage systems for shared enterprise storage environments, which are designed to provide scalable performance for various enterprise class applications. Such storage systems may for instance comprise modules that contain storage devices such as NAND Flash devices. These modules are mounted in a structure (e.g., a frame or a metal cage) having specific dimensions, which may be standardized. Such dimensions cannot always easily be changed for any new generation of devices (e.g., chip packages) and modules thereof. In some cases, the dimensions of the device packages and resulting modules cannot be reconciled with the requirements of the legacy structures (e.g., the cages), which obliges manufacturers to develop new formats for the outer structures.